TEM study of 101̄0 inversion domains in GaN layers grown on (0001) sapphire substrate

The atomic structure of nanometric inversion domains in GaN layers has been investigated using high resolution electron microscopy and image simulation. These domains are limited by 101̄0 planes; they cross the whole epitaxial layers until the surface in the center of small pyramids. For image simulation, six models were considered and a good agreement with the observations was obtained for a model characterized by an inversion and a c/2 translation.